The American Pit Bull Terrier (APBT) is a purebred dog breed recognized by the United Kennel Club and American Dog Breeders Association, but not the American Kennel Club (AKC). It is a medium-sized, solidly-built, intelligent, short-haired dog, whose early ancestors came from the British Isles. When compared with the English Staffordshire Bull Terrier, the American Pit Bull Terrier is larger by margins of 6–8 inches (15–20 cm) in height and 25–35 pounds (11–16 kg) in weight. The American Pit Bull Terrier varies in size. Males normally are about 18-21 inches (45–53 cm) in height and around 35-60 pounds (15–27 kg) in weight. Females are normally around 17-20 inches (43–50 cm) in height and 30-50 pounds (13–22 kg) in weight.